1. Technical Field
This invention relates to a novel method for sealing high density electronic circuits, such as, integrated circuits, by positioning the circuit on a pedestal in the interior of a container. The container is filled with a hydrophobic liquid sufficiently to immerse the circuit and form a bubble at the top of the container.
2. Background Information
High density electronics, such as, integrated circuits, hybrids circuits, optical-electronics, etc. are increasingly manufactured with thin-film metals, such as gold, aluminum, nickel etc.. When the metals are exposed to ionic contaminants, temperatures and electrical voltage; corrosion causes a degradation in electrical performance. Protection against corrosion is provided by isolating the material against moisture. This is accomplished by applying a protective coating on the electronic circuits such as silicon dioxide, silicon Nitride epoxy and the like. Protection is also provided by positioning the electronic circuit in a moisture resistant container constructed of metal, glass, or a ceramic. These containers are generally assembled from two or more parts sealed by soldering, welding or glass bonding process.
MIL-STD 1014 is one standard for testing/qualifying leakage rates of hermetically sealed microcircuits. In this test containers are allowed to have leak rates up between 1.times.10.sup.-7 and 5.times.10.sup.-8 atm-cm/sec (volume dependent). This, however has been shown to allow moisture penetration sufficient to cause failure of the device by corrosion within 1 year. Consequently, even though a device has passed this test, its extended life is unknown.